President Trump called Iran "a terrorist nation like few others" during remarks Friday morning to a gathering of social conservatives in Washington, just hours before he was expected to say Iran is not complying with former President Barack Obama's nuclear agreement.

"This afternoon, in a little while, I'll be giving a speech on Iran, a terrorist nation like few others, and I think you're going to find it very interesting," Trump told a Values Voter Summit audience in a hotel ballroom.

Trump is expected not to certify that Iran is in compliance with an Obama administration-negotiated nuclear deal with the country, which could prompt Congress to reimpose sanctions.

Trump called the deal an embarrassment to the U.S. during a September speech to the United Nations General Assembly, but decertifying the deal won't necessarily kill it.

The president also is expected to discuss Iran's Revolutionary Guards Corps, which has assisted the governments of Iraq and Syria in fighting rebels and Islamic State terrorists, but which also is allied with the Lebanese Hezbollah movement and historically has engaged in terrorism.

Trump received loud applause during his Values Voter Summit speech for mentioning "our cherished friend and partner, the state of Israel" and saying "in this administration, we call evil by its name."

"We take decisive action against those who would threaten our people with harm, and we will be decisive," Trump said.